| 摘要 |
<p>Fuel pump (3) draws fuel, from tank (2) and delivers it (4,6), via regulator (5), to engine (7). Regulator returns excess fuel (8) to pump. Space above fuel in tank is vented to atmosphere by vapor venting valve (1), with whose interior it communicates. Generally tubular valve body (27) has central top outlet (16)' leading to exterior, and houses coaxially (X) mobile cylinder (10), sliding vertically on guide ribs formed on its interior wall. The cylinder has a concave base (17) resting on a supporting ledge (14), just above a central vertical nozzle (11) connected to the fuel return pipe (8). In this position, during refueling, air and vapor displaced by incoming fuel can pass freely through base apertures (13), gaps in the support ledge, channels (29) between guide ribs and the top outlet (16), into the venting pipe (15), where an active carbon filter traps the fuel vapors. When the tank is full, the valve cylinder floats up against and closes the outlet, creating back pressure that stops the service station fuel delivery. Though the level falls as fuel is consumed, so long as the engine is running the valve remains closed because excess fuel returned by the regulator issuing from the nozzle (11) impinges on the concave valve cylinder base (17). An Independent claim is also included for the fuel tank.</p> |
